Ji-Xin Cheng, the Moustakas Chair Professor in Photonics and Optoelectronics, has been named the 2022 Boston University Innovator of the Year.
Cheng has a long list of trailblazing achievements, including inventing a way to use blue light and hydrogen peroxide to treat a drug-resistant skin infection called MRSA, finding molecular signatures associated with aggressive cancers for treatment and diagnosis, and creating novel imaging techniques using infrared light to see molecules inside living cells. A BU College of Engineering professor of biomedical engineering, electrical and computer engineering, and materials science and engineering, his specialty is bond-selective imaging, which allows scientists to see cells on the molecular level without injecting a visible dye (dye particles are larger than molecules, interfering with their chemical makeup). He recently received funding from the Chan Zuckerberg Initiative to develop a new dye-free technique, called bond-selective intensity diffraction tomography, which can produce a three-dimensional map of a specific chemical inside cells. This has the potential to help scientists unlock knowledge for treating diseases, from cancer to Alzheimer’s.
“I have been keeping BU’s Technology Development office very busy,” Cheng says. Each year, Technology Development, which helps faculty commercialize their research, gathers nominations from the BU community to select the Innovator of the Year award. This year’s award was announced at an in-person celebration on May 1 and presented to Cheng by Kenneth R. Lutchen, ENG dean and a professor of biomedical engineering.
To learn more about where he gets his inspiration, The Brink sat down with Cheng to talk about his journey as a scientist and inventor.
with Ji-Xin Cheng
The Brink: Why do we want to see into cells?
Cheng: To understand the nature of life. The molecules in the cell are highly organized and work together to drive, produce energy, produce membranes, divide, but exactly how so many molecules work inside cells is not clear. If we can understand this, we can understand the fundamentals inside the cells. It is also very important for disease diagnosis and treatment—when a cell becomes a cancer cell, we want to understand if there is new chemistry happening in the cancer cell, which can be a signature for cancer diagnosis.
My team has made many discoveries. For example, using coherent Raman scattering microscopy, of which I am a coinventor, we discovered a molecular signature for aggressive prostate cancer in 2014. It helps distinguish aggressive prostate cancer versus a benign tumor. With label-free imaging, we can directly study the human sample and look into the cell, which is beyond the reach of fluorescence microscopy. We find that the signature is not everywhere, it’s localized in one particular position of the cell.
The Brink: With so many different aspects of your work, what are you focusing on now and hoping to accomplish next?
Cheng: We do many things—I’m not limiting myself to imaging. In collaboration with my BU colleague Chen Yang and others, I recently started in a new direction called optoacoustic neuromodulation. Scientists want to make new tools to control the behavior of the brain. This happens now with a technique called optogenetics, but it has one problem: it needs a virus to deliver a gene for this technique to work. That means a viral particle delivers a gene to the neuron—this is done in mice, but you don’t want to inject a viral particle in a human. So, we’re asking, can we do this genetics-free?
The Brink: Like a safe alternative version for humans?
Right. We had the idea of converting optogenetics—which is optical, using light to stimulate the neuron—to an opto-mechanical technique. That way, we can perturb the neuron membrane and it will fire—this is what we’re calling optoacoustic, so it converts an optical wave to an ultrasound wave to produce brain stimulation. One goal is to do this for treatment of human patients. We’re working with a Paris-based company, Axorus, to apply this technique for retinal stimulation. It’s in the early stages, but the scientific principle works. This can help a lot of people if we can turn this into a real device. It will take another 8 to 10 years.
The Brink: How did you first get started in this field?
I was trained as a physical chemist as a PhD student and postdoc. I was looking for a job in 2003 and had one offer from the chemistry department at the University of Utah. I then got an offer from Purdue University in biomedical engineering, and I had no idea what biomedical engineers do—I talked to my advisor at Harvard University and he said, “Oh they make artificial bones.” So, that was my initial understanding of biomedical engineering. Photonics was still new and eventually became a major direction, but the whole biomedical engineering department at Purdue only had six faculty at the time. It turned out to be a very good decision for me to go there, because I was able to bring my spectroscopy knowledge into the biomedical engineering discipline. I had the fortune of leading an emerging field called chemical imaging. A major goal of my career is to build a special microscope, called a chemical microscope, which allows scientists to map molecules inside a living system without dye labels.
The Brink: What would you say to early career scientists who want to be innovators? What advice would you give them?
The whole world can be described in one word: change. Innovation means that you do new things, and the whole world is changing every day. If you don’t change, you cannot do new things. And embracing change, in my case, is having no fear to enter a new field, or a new discipline. That will create unexpected opportunity. The flip side to my advice is to not change—that’s exactly the Chinese philosophy, the yin and yang, change and no change. Here, no change means persistence. Because if you want to have a big impact, you need to have persistence toward a far-reaching goal and never give up. I have a dream to make dye-free bond-selective microscopy extremely sensitive, to be on par with fluorescence microscopy, which has single molecule detection. That way we can really see molecules, since the concentration of most molecules inside cell tissue is very low. We are now very close to that dream, from not giving up and having no fear of trying new ways over the past 20 years.
This interview was edited and condensed for clarity.